Physio Final Pt. 2

1. which best describes the process of "adaptation" in sensory receptors?

a. information from sensory receptors reaches the cerebral cortex and the person becomes away of it

b. conversion of the energy of a stimulus into a pattern of electrical activity

c. persistance of the sensation of a limb even after it has been severed from the body

d. a decrease in receptor sensitivity despite continuation of a stimulus

e. a depolarization of receptive membrane that increase in magnitude as the stimulus intensity increases

2. which of the following is most important for the determination of stimulus type?

a. the relative sensitivity of different receptors to different stimulus energies

b. the intensity of a stimulus

c. the location on the body where a stimulus is applied

d. propagation of a signal along a nonspecific ascending pathway

3. which of the following statments regarding the determination of stimulus intensity is true?

a. stronger intensity stimuli case rapid adaptation, while weaker stimuli cause slower adaptation

b. the amplitude of action potentials increases with increasing stimulus intensity

c. the duration of receptor potentials decreases with increasing stimulus intensity

d. the frequency of action potentials increases with increasing stimulus intensity

e. the only means of detecting intensity changes is through recruitment of greater numbers of sensory units

4. which is an accurate description of the corticol association areas?

a. they are all found in the parietal lobe of the cerebral cortex

b. they integrate multiple types of sensory information and are responsible for complex processing of sensory information

c. their main input is sensory information arriving along neurons that project directly from the thalamus

d. none of the above

5. which of the following statements regarding the precision (acuity) of locating a somatic stimulus is FALSE?

a. the precision is greater in the lips and fingers than on the back

b. the precision is greater for the internal organs than for the skin

6. which of the following would NOT be categorized as a "somatic" sensation?

a. pressure

b. cold and warmth

c. sound

d. proprioception

7. which of the following statements regarding sensory pathways is correct?

a. all somatic sensory information that reaches the cerebral cortex is first processed in the thalamus

b. somatic sensory information from the left side of the body projects to the left side of the somatosensory cortex

c. all somatic sensory information travels together in a single tract in the spinal cord

d. ascending pathways in the anterolateral column of the spinal cord carry information about fine touch discrimination

e. ascending pathways in the dorsal column of the spinal cord carry information about pain from the back muscles

8. which of the following symptoms would a patient with a lesion that destroyed the right side of the spinal cord in the region of the neck be most likely to experience?

a. loss of both pressure and sense and pain in the right foot

b. loss of both pressure sense and pain in the left foot

c. loss of pressure sense in the right foot and pain in the left foot

d. loss of pressure sense in the left foot and pain in the right foot

9. accommodation for near vision requires:

a. flattening of the lens

b. contraction of he ciliary muscles

c. activation of the sympathetic nervous system

d. increased rounding of the cornea

e. dilation of the pupil

10. during normal viewing of a distant object, the

a. firing a parasympathetic nerves to ciliary muscles increases

b. suspensory ligaments are slackened

c. lens flattens

d. light rays striking the eyes are diverged by the cornea

e. ciliary muscles are contracted

11. a person whose lens focuses light from distant objects in front of the retina has a condition called

a. presbyopia

b. hyperopia

c. myopia

d. cataract

e. glaucoma

12. which of the following statements about rods and cones in the retina is TRUE?

a. cones enable us to see in dim light; rods provide color vision

b. rods and cones all have the same kind of opsin

c. cones are found in highest density in the fovea; rods are more prevalent near the edges of the retina

d. rods require brighter light to activate them than do cones

e. rods provide higher visual acuity than do cones

13. which of these occurs when light strikes photoreceptors?

a. the retinal undergoes a change of shape

b. there is an increase in neurotransmitter release from photoreceptor cells

c. the photoreceptor cell membrane becomes depolarized

d. the concentration of cyclic GMP inside cells increases

e. the photoreceptor cells are stimulated and fire action potentials

14. the plasma membranes of rod and cone cells are

a. at their resting potential in the dark and depolarized in the light

b. at their resting potential in the dark and hyperpolarized in the light

c. depolarized in the dark and hyperpolarized in the light

d. hyperpolarized in the dark and at their resting potential in the light

e. hyperpolarized in the dark and depolarized in the light

15. each of the following statements regarding vision is true. which statement best explains why we cannot see colors in dim light?

a. the human eye has three kinds of cone photoreceptors

b. there are six types of opponent color cells in the lateral geniculate nucleus

c. the human eye has only one kind of rod photoreceptor

d. cone photoreceptors are concentrated in the fovea

16. in the visual pathway providing sensory action potentials to the brain, the first cells which are capable of initiation action potentials are

a. cone cells

b. rod cells

c. lateral geniculate cells

d. ganglionic cells

17. the actual receptors for hearing are called:

a. baroreceptors

b. nociceptors

c. hair cells

d. pacinian corpuscles

e. somatic receptors

18. where are receptors for the chemical senses located?

a. in the organ of corti and saccule

b. in the cochlea and lateral geniculate nucleus

c. in the skin and tendons

d. in the tongue and nose

e. in the fovea and semicircular canals

19. the phenomenon known as referred pain

a. is a perception of a false painful stimulus with no initiating stimulus; it is created in the mind

b. is a direct association of an activity, which is on the verge of causing tissue damage to its specific location and cause in the body

c. is the projected perception of pain as a sensation being experienced at a site other than that of the actual injured or diseased tissue

d. is synonymous with the persistance of perception of painful stimuli long after the activity responsible for triggering them has ceased

20. the process by which sensory receptors change various forms of energy into electrical energy is called translocation

a. true

b. false

21. "somatosensory" refers to the part of the cerebral cortex that receives synaptic input from specific ascending pathways originating only with receptors for tough

a. true

b. false

22. in the somatosensory cortex. neuronal representation of body parts is proportional to the size of the body part

a. true

b. false

23. the precision of locating a somatosensory stimulus is greater in areas of the body that have small, overlapping receptive fields than in areas with large, nonoverlapping fields.

a. true

b. false

24. gamma-aminobutyric acid (GABA) is a major excitatory transmitter in the central nervous system

a. true

b. false

25. the lateral axons of optic nerves from each eye cross at the optic chiasm, so all visual information from the right eye is received by the left side of the brain

a. true

b. false

26. axons of ganglion cells from the retina synapse in the medial geniculate nucleus of the thalamus on the way to the occipital lobes

a. true

b. false

27. the photoreceptor cell is different from other sensory receptors in that is is the only type that is actually depolarized at rest

a. true

b. false

28. what category of receptors do pacinian corpuscles belong to

a. mechanoreceptors

b. chemoreceptors

c. nociceptors

d. photorecepetors

29. which is false about neurons

a. a given neuron can be either a presynaptic neuron or postsynaptic neuron

b. an individual neron can receive information from multiple other neurons

c. an individual neuron can transmit information to multiple other neurons

d. a neuron can simutaneously release more than one type of a neurotransmitter

e. a neuron receives information on its axons and delivers it to other neurons through its dendrites

30. which is true about typical, resting neurons?

a. the plasma membrane is most permeable to sodium ions

b. the concentration of sodium ion is greater inside the cell than outside

c. the permeability of the plasma membrane to potassium ions is much greater than its permeability to sodium ions

31. a threshold stimulus applied to an excitable membrane is one that is just sufficient to:

a. trigger an action potential

b. be conducted to the axon hillock

c. depolarize a dendrite

32. which must happen in order for an action potential to begin?

a. the membrane potential must be at the Na+ equilibrium potential

b. Na+ influx must exceed K+ efflux

c. the membrane must be out of the relative refractory period

d. Na+ channels must all be inactivated

33. during the rising (depolarizing) phase of a neuronal action potential

a. permeability of K+ becomes much greater than permeability Na+

b. permeability Na+ becomes much greater than permeability K+

c. permeability K+ is the same as permeability Na+

d. Na+ efflux (flow out of the cell) occurs

e. K+ flows rapidly into the cell

34. suppose that all calcium could be removed from the extracellular fluid surrounding a neuron. such removal would inhibit the ability of a neuron to

a. produce action potentials

b. release neurotransmitter

c. respond to the binding of a neurotransmitter to its receptor

d. degrade neurotransmitter

35. synaptic vesicles

a. store calcium

b. release NT by exocytosis

c. degrade NT

d. form gap junctions

e. synthesizes NT

36. if Na+ channels closed in response to a stimulus, then

a. the neuron would be depolarized

b. the neuron would be hyperpolarized

c. none of the above

37. which is most directly responsible for the falling (repolarizing) phase of the action potential?

a. voltage-gated Na+ channels are opened

b. the Na+ K+ pump restores the ions to their original locations inside and outside of the cell

c. the permeability to Na+ increases greatly

d. ATPase destroys the energy supply that was maintaining the actin potential at its peak

e. the permeability to K+ increases greatly while that to Na+ decreases

38. which of the following statements about eh refractory period of a membrane is true?

a. the absolute refractory period refers to the period of time during which another action potential cannot be initiated in that part of the membrane that is undergoing an action potential, no matter how great the strength of the stimulus

b. the refractory period prevents the action potential from spreading back over the part of the membrane that just underwent an action potential

c. all of the above choices are correct

39. which of the following statements regarding action potentials generated in a neuronal membrane is not true?

a. action potentials travel decrementally down the membrane

b. an action potential generates a new action potential in an ajacent area of membrane

c. an action potential generates a local current that depolarizes adjacent membrane to threshold potential

d. action potentials are usually initiated at the initial segment of a neuron

e. an action potential generated by a threshold stimulus is the same size as on generated by supra-threshold stimulus

40. How is the strength of a stimulus encoded by neurons?

a. by the size of action potentials

b. by the frequency of action potentials

c. by the duration of action potentials

41. which of the following statements concerning the rate of action potential propagation is true?

a. it is faster in small-diameter axons than in large-diameter axons

b. it is faster for a strong stimulus than for a weak one

c. it is faster in myelinated axons than in nonmyelinated axons

d. it is faster in the dendrites than in the axon

e. it occurs at the same rate in all axons, regardless of their diameter

42. which of the following is not known to be an important neurotransmitter in the CNS?

a. dopamine

b. acetylcholine

c. morphine

d. glutamate

43. which of the following statements about acetylcholine is correct?

a. acetylcholine binds to nicotinic and muscarinic receptors

b. acetylcholine binds to adrenergic receptors

c. acetylcholine is the neurotransmitter released by most sympathetic postganglionic neurons

d. acetylcholine is generally transported back into presynaptic nerve terminals without being enzymatically degraded

44. norepinephrine is a neurotransmitter and binds to adrenergic receptors

a. true

b. false

45. nicotine is

a. cholinergic antagonist

b. a neurotransmitter

c. a cholinergic agonist

46. which is one of the most abundant excitatory neurotrnsmitters in the CNS?

a. glutamate

b. do

c. norepinephrine

d. gamma-aminobutyric acid (GABA)

47. the portion of the peripheral nervous system that is composed of nerve fibers that innervate skeletal muscle is called the:

a. afferent nervous system

b. sympathetic nervous system

c. parasympathetic nervous system

d. somatic motor nervous system

e. autonomic nervous system

48. the maintenance of a resting potential in a neuron depends not only upon the functioning of the Na+/K+ pumps in the membrane

a. true

b. false

49. at an excitatory chemical synapse between two neurons

a. there is increased permeability of the postsynaptic cell to both Na+ and K+

b. a small hyperpolarization of the postsyaptic membrane occurs when the synapse is activated

c. an action potential in the presynaptic neuron always causes an action potential in the postsynaptic neuron

d. excitation occurs because K+ enters the postsynaptic cell

e. action potentials spread through gap junctions between cells

50. an inhibitory postsynaptic potential (IPSP)

a. is produced by simultaneous increases in permeability to both Na+ and K+

b. occurs when a ligand-gated channel increases its permeability to K+

c. is a small depolarization in a postsynaptic cell

d. can be summed with other IPSPs to trigger an action potential in the postsynaptic cell

e. is produce by an increase in permeability to only Na+

51. EPSPs depolarize postsynaptic cell membranes

a. true

b. false

52. which of these is a lipid soluble messenger?

a. thyroid hormone

b. protein kinase

c. glucose

d. sodium

e. cyclic AMP

53. specificity is an important characteristics of intercellular communication and it occurs because protein chemical messengers are only expressed in specific target cells

a. true

b. false

54. direct communication between cells in contact with one another is accomplished through

a. ligands

b. receptors

c. gap junctions

d. paracrine messengers

e. endocrine hormones

55. the number of bound receptors on a target cell depends on the concentration of messengr and the counter receptors

a. true

b. false

56. which type of chemical messenger, when released, binds to receptors on the cell that released the chemical messenger?

a. hormone

b. autocrine

c. neurotransmitter

57. Which of the following chemical messengers is lipophilic and therefore able to cross the cell membrane?

a. amino acids

b. amines

c. peptides

d. eicosanoids

e. proteins

58. the location of receptors on a target cell depends on the solubility of the chemical messenger. Where would the receptors for lipophilic messengers be located?

a. on the outside of the cell

b. on the inside of the cell

c. only in the nucleus

59. Lipophobic chemical messengers communicate a message to the target cell by binding to receptors on that cell's membrane.

a. true

b. false

60. In its active form, a G protein has a GDP bound to its alpha unit.

a. true

b. false

61-64. Put in order the components of the general pathway of a signal transduction

61. first

62. second

63. third

64. fourth

a. response

b. chemical messenger

c. target proteins

d. receptor proteins

65-69. match the following chemical messengers to their chemical structure classification

65. amines

66. peptides

67. eicosanoids

68. steroids

69. amino acids

a. aldosterone

b. glycine

c. cathecolamines

d. thromboxanes

e. glucagon

70. tyrosine kinase catalyzes phosphorylation of intracellular protein

a. true

b. false

71-75

71. it dissolves in blood

72. it secreted by simple diffusion

73. it alters transcription of mRNA

74. it could be an amino acid, amines, or peptide

75. receptors found in cytosol or nucleus

a. lipophobic messenger

b. lipophilic messenger

76-78

76. critical level where membrane potential is depolarized to initiate action potential

77. difference of voltage between the inside and the outside of the cell

78. large and rapid changes in membrane potential, inside is more positive

a. membrane potential

b. resting membrane potential

c. threshold potential

d. action potential

e. transduction

79. EPSPs can occur as either fast or slow responses

a. true

b. false

80. when voltage-gated Ca++ channels open, Ca++ moves out of the cell

a. true

b. false